More time for Covid to spread as people infectious for longer than expected

Two-thirds of people with mild Covid-19 are still infectious five days after their symptoms begin, according to a London study.

Research has revealed people are infectious with Covid-19 beyond the guidance of five days.

Two-thirds of people with mild Covid-19 are still infectious five days after their symptoms begin, according to a study.

The research revealed people spread the virus for longer than previously thought, contrary to guidance that states “many will no longer be infectious to others after five days”.

The study by Imperial College London suggests this five-day period is not long enough to cut transmission. In the first real-world study of its kind, ­experts monitored 57 people at home after they were exposed to Covid-19.

Only one in five were infectious before their symptoms developed, but two-thirds of cases were still infectious five days after first reporting symptoms.

Professor Ajit Lalvani, the lead author, said: “The NHS currently advises that if you test positive for Covid-19 you should try to stay at home and avoid contact with other people for five days, but our data suggests that under a crude five-day self-isolation period two-thirds of cases released into the community would still be infectious – though their level of infectiousness would have substantially reduced.”